Our friends at ecogeek point us to the Windscraper, designed by David Fisher. The Windscraper is a self powered building where each floor spins independently in the sky. The result is that Windscraper can power itself along with 10 other similarly sized buildings. BONUS: The more dizzy you get, the more power you're generating.
I'm not sure if I'm sold by the spinning floor 'thing', but the idea of a self sustaining building is intriguing. For a more feasible design, check out the Bahrain World Trade Center, a building with Integrated Wind Turbines.